1. Field of the Invention
The present invention relates to a system and method for managing frequency resources, and more particularly to a system and method for dynamically allocating and managing frequency resources under an environment of multiple radio access networks (RAN).
2. Description of the Related Art
In the fourth-generation (4G) communication system, it is expected that various radio access networks coexist, so an efficient resource management method is required. Accordingly, frequency band allocation for new services and efficient frequency resource management have emerged as hot issues.
The conventional methods for managing frequency resources in multiple radio access networks include a fixed spectrum allocation (FSA) method and a dynamic spectrum allocation (DSA) method.
According to the FSA method, frequency resources are allocated in the same ratio regardless of the loads on radio access networks. The FSA method allocates frequency resources in the same manner without taking into consideration the service characteristics. Therefore, the FSA method is inefficient in resource management.
For this reason, the DSA method measures the load on each radio access network and dynamically allocates frequency resources in proportion to the measured load so as to efficiently manage the resources. In addition, according to the DSA method, when frequency resources of requested frequency bands between radio access networks collide with each other, a specific radio access network can be given priority or a radio access network can be randomly selected to be allocated with frequency resources. However, the frequency resource allocation according to the DSA method is performed in consideration of only loads measured according to radio access networks, without taking into consideration priority between radio access networks, priority between service classes and also the possibility of negotiation between radio access networks. Accordingly, the DSA method also has difficulty in efficiently managing frequency resources.